Struct TriGridLayout

Defines the spatial layout for a triangular grid, encapsulating the triangle edge length and world-space origin required to convert between TriCoord lane coordinates and Unity world-space Vector2 positions.

Implements
Inherited Members
Namespace: Scylla.Core.Structures
Assembly: ScyllaCore.dll
Syntax
public readonly struct TriGridLayout : IEquatable<TriGridLayout>
Remarks

The forward transform (GridToWorld(TriCoord)) computes the centroid of a triangle from its lane coordinate using the following formulae, where L is EdgeLength: 

x = (0.5·A - 0.5·C) · L + OriginX
y = (-√3/6·A + √3/3·B - √3/6·C) · L + OriginY

The inverse transform (WorldToGrid(Vector2)) maps a world position back to the nearest triangle by ceiling/floor lane detection.

All three constructor parameters are validated to be finite numbers; non-finite or zero EdgeLength values throw ArgumentOutOfRangeException.

Constructors

TriGridLayout(float, float, float)

Creates a new triangle grid layout with the specified edge length and world-space origin.

Declaration
public TriGridLayout(float edgeLength, float originX = 0, float originY = 0)
Parameters
Type Name Description
float edgeLength

The edge length of each equilateral triangle in Unity world units. Must be a finite number strictly greater than zero.
float originX

The X world-space position of the grid origin. Defaults to 0. Must be a finite number.
float originY

The Y world-space position of the grid origin. Defaults to 0. Must be a finite number.
Exceptions
Type Condition
ArgumentOutOfRangeException

Thrown when edgeLength is not a finite positive number, or when originX or originY is NaN or infinite.

Fields

EdgeLength

The edge length of each equilateral triangle, measured in Unity world units. This value scales all coordinate-to-world conversions uniformly.

Declaration
public readonly float EdgeLength
Field Value
Type Description
float

OriginX

The X component of the world-space origin of the grid's coordinate system. Triangle centroids are offset by this amount along the X axis.

Declaration
public readonly float OriginX
Field Value
Type Description
float

OriginY

The Y component of the world-space origin of the grid's coordinate system. Triangle centroids are offset by this amount along the Y axis.

Declaration
public readonly float OriginY
Field Value
Type Description
float

Methods

Equals(TriGridLayout)

Determines whether this layout is identical to another layout by performing exact floating-point equality on all three parameters.

Declaration
public bool Equals(TriGridLayout other)
Parameters
Type Name Description
TriGridLayout other

The layout to compare with.
Returns
Type Description
bool

true if EdgeLength, OriginX, and OriginY are all bitwise-equal; false otherwise.
Remarks

This comparison uses exact == equality on floating-point values, which is intentional - layouts are considered equal only when constructed with the same literal values. Use this when matching cached layout instances, not for detecting "approximately same" layouts.

Equals(object)

Determines whether this layout equals another object.

Declaration
public override bool Equals(object obj)
Parameters
Type Name Description
object obj

The object to compare with.
Returns
Type Description
bool

True if the object is a TriGridLayout with equal values.
Overrides

GetHashCode()

Returns a hash code for this layout.

Declaration
public override int GetHashCode()
Returns
Type Description
int

A hash code based on all layout parameters.
Overrides

GridToWorld(TriCoord)

Converts a triangle lane coordinate to the world-space position of the triangle's centroid.

Declaration
public Vector2 GridToWorld(TriCoord coord)
Parameters
Type Name Description
TriCoord coord

The triangle lane coordinate to convert.
Returns
Type Description
Vector2

The world-space Vector2 position of the centroid of the triangle identified by coord.
Remarks

The conversion applies the following formulae (where L = EdgeLength):

x = (0.5·A - 0.5·C) · L + OriginX
y = (-√3/6·A + √3/3·B - √3/6·C) · L + OriginY

Both upward and downward triangles produce their respective centroid positions.

ToString()

Returns a human-readable string representation of this layout.

Declaration
public override string ToString()
Returns
Type Description
string

A string in the format TriGridLayout(Edge: {EdgeLength}, Origin: ({OriginX}, {OriginY})).
Overrides

WorldToGrid(Vector2)

Converts a world-space position to the TriCoord of the triangle that contains or is nearest to that position.

Declaration
public TriCoord WorldToGrid(Vector2 worldPos)
Parameters
Type Name Description
Vector2 worldPos

The world-space position to convert.
Returns
Type Description
TriCoord

The TriCoord of the triangle that contains worldPos.
Remarks

The algorithm normalises the world position by the edge length and origin, then uses ceiling and floor lane detection to snap to the enclosing triangle: 

px = (worldPos.x - OriginX) / EdgeLength
py = (worldPos.y - OriginY) / EdgeLength
A = ceil(px - √3/3 · py)
B = floor(2√3/3 · py) + 1
C = ceil(-px - √3/3 · py)

The returned coordinate is always a valid triangle (A + B + C equals 1 or 2) for any finite input position.

Operators

operator ==(TriGridLayout, TriGridLayout)

Returns true when left and right have identical edge length and origin values.

Declaration
public static bool operator ==(TriGridLayout left, TriGridLayout right)
Parameters
Type Name Description
TriGridLayout left

The left operand.
TriGridLayout right

The right operand.
Returns
Type Description
bool

true if both layouts are equal; otherwise false.

operator !=(TriGridLayout, TriGridLayout)

Returns true when left and right differ in at least one parameter.

Declaration
public static bool operator !=(TriGridLayout left, TriGridLayout right)
Parameters
Type Name Description
TriGridLayout left

The left operand.
TriGridLayout right

The right operand.
Returns
Type Description
bool

true if the layouts are not equal; otherwise false.

Implements

See Also